According to the Center for Disease Control (CDC), over sixty percent of the United States population is overweight, and almost twenty percent are obese. This translates into about 38.8 million adults in the United States with a Body Mass Index (BMI) of 30 or above. The BMI is generally defined as the weight (e.g., in kilograms) of an individual divided by the height (e.g., in meters) of the individual, squared. To be considered clinically, morbidly obese, one must meet one of three criteria: BMI over 35, 100 lbs. overweight, or 100% above ideal body weight. There is also a category for the super-obese for those weighing over 350 lbs.
Obesity is thus an overwhelming health problem in the U.S. Moreover, because of the enormous strain associated with carrying this excess weight, organs are affected, as are the nervous and circulatory systems in an individual who is overweight or obese. In 2000, the National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) estimated that there were 280,000 deaths directly related to obesity. The NIDDK further estimated that the direct cost of healthcare in the US associated with obesity is $51 billion. In addition, Americans spend approximately $33 billion per year on weight loss products. In spite of this economic cost and consumer commitment, the prevalence of obesity continues to rise at alarming rates. From 1991 to 2000, obesity in the US grew by about 61%. Not exclusively a US problem, worldwide obesity ranges are also increasing dramatically.
There have been many attempts in the past to surgically modify anatomies of a patient to address the consumption problem by reducing the desire to eat. Stomach staplings, or gastroplasties, in order to reduce the volumetric size of the stomach, therein achieving faster satiety, were initially performed in the 1980's and early 1990's. Although able to achieve early weight loss, sustained reduction in connection with gastroplasties was not obtained. The reasons are not all known, but are believed to be related to several factors. One of which is that the stomach stretches over time, thereby increasing volume, while psychological drivers motivate patients to find creative approaches to literally eat around the smaller pouch.
Space-occupying gastric balloons have also been used to treat obesity since the 1980's. One such balloon is described by Garren et al. (U.S. Pat. No. 4,899,747 Method and apparatus for treating obesity). Gastric balloons are generally designed to decrease the functional volume of the stomach.
Similarly, intestinal sleeves are also being used for obesity treatment (Levine et al., U.S. Pat. No. 7,347,875 Methods of treatment using a bariatric sleeve; Levine et al. U.S. Pat. No. 7,025,791 Bariatric sleeve). These sleeves consist of an anchoring mechanism that attaches at one end of a thin walled plastic sleeve and extends from the pylorus to allow the sleeve to extend past the Ligament of Treitz. Intestinal sleeves function to decrease absorption from the portion of bowel covered by the sleeve. Presently, a guidewire is advanced into the patient's jejunum under fluoroscopic guidance (Gersin K S, Keller J E, Stefanidis D, et al. Duodenal jejuna bypass sleeve: A totally endoscopic device for the treatment of morbid obesity. Surg Innov 2007:14; 275). A gastroscope is then used to deploy the stent-like anchor in the pylorus, and gastroscopic instruments; e.g. graspers, are used to hold the sheath and advance it along the intestine to the Ligament of Treitz. However, complications often associate with delivery of intestinal sleeves. In addition, the sleeves are difficult to manipulate, and especially the current methods for advancing the sleeves along the intestine are time consuming and inefficient.
In another approach, an open bariatric surgical procedure known as the “Roux-en-Y” procedure, a small stomach pouch is created by stapling part of the stomach together.
This small pouch can limit how much food an individual can eat. In addition, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the duodenum as well as the first portion of the jejunum. This causes reduced calorie and nutrient absorption. Common problems associated with Roux-en-Y include pouch stretching, where the stomach gets bigger overtime and can stretch back to its original size over time; a breakdown of staple lines where the staples fall apart and reverse the procedure; and a leakage of stomach contents into the abdomen (this is dangerous because the acid can eat away other organs. In addition, as the Roux-en-Y procedure requires open surgery, it is a painful, time-consuming operation and requires relatively long recovery time.
Accordingly, it would be desirable to have an effective system for bariatric therapy, reducing the harmful side effects such as painful surgical operations. In particular, there is a need for effective systems and delivery mechanisms for bariatric therapy that can minimize complications and recovery time, reduce operation time and resources, and improve therapy efficiency, success rate, and safety.